Sharpening device for cloth-cutting machines



F. J. CLARK.

SHARPENING DEVICE FOR CLOTH CUTTING MACHINES. APPLICATION FILED DEC. 16. 191B.

1,368,321.- Patented Fe 15, 1921.

2 SHEETS-SHELL a ATTORNEYJ.

. F. I. CLARK.

SHARPENING DEVICE FOR mom cuuma IiIlAjCfiINES. APPLICATION FILED DEC. 16; IBM}. l gfiifi 3231, Paivsz tfid FGIJ. 15, 1921.

2 SHETS-SHEET 2- UNITED STATES PATENT @FFECE.

FREDERICK J. CLARK, OF BUFFALO, NEW YORK, ASSIGNOR TO EASTMAN MACHINE 00., OF BUFFALO, NEVZT YORK.

SHARPENING DEVICE FOR CLOTH-CUTTING MACHINES.

Application filed December 16, 1918.

adapted to be moved about by hand on the cutting table to cause the knife to follow apattern on the lay of cloth or material being cut.

These machines are commonly equipped with a sharpening deviceconsisting of a pair of rotary emery or grinding wheels which are adapted to be pressed against the oppo site sides of the edge of the knife and are driven by engagement with the rotating knife, thereby grinding or sharpening the edge. The sharpener'has to be adjusted to different operative positions from time to time as the knife wears and decreases in diameter, and in, the sharpeners as heretofore constructechnmch difliculty has been experienced in getting the unskilled users of the machines to adjust the sharpener to the position relative to the :knife required to insure proper sharpening of theedge. If the grinding wheels are adjusted outwardly too far in front of the edge of the knife, they are apt to turn over theedge or-make the bevel too abrupt, whereas if the wheels are adjusted inwardlybeyond the proper point they will form a thin feather edge which will readily nick or break off.

One object of the invention isgto provide an eflicicnt sharpenerof simple and inexpensive construction having meanswhich .ena-blesthe operator to quickly and easily adjust the sharpenerto' proper sharpening re lation tothe knife and avoidithe above mentioned dih'iculties heretofore experienced, simply by, seeing that an' indicator bears a prescribed relation to theedgeof the knife.

Another object is -to improve thessharpeners of cloth cutting machines-in the; other respects hereinafter described. and. setforth int-lieg'claims.

Iii-the accompanying-drawings Figure 1 is aside elevation ofanlelectric clothcutting anachine provided with knifesharpeningmeans embodying the invention.

Specification of Letters Patent.

Patented Feb. 15, 1921.

Serial No. 266,888.

Fig. 2 is a similar elevation enlarged, of the sharpener.

Fig. 3 is a front elevation of the sharpener showing it in operative position relative to the knife.

Fig. 4 is a similar view showing the inoperative position of the sharpener.

Fig. 5 is a plan view, partly in section, of the adjustable support for the sharpener.

Fig. 6 is a fragmentary elevation showing the catch for holding the sharpener in the inoperative position.

The cloth cutting machine comprises, as usual, a flat base A adapted to rest and move upon the cutting table or other suitable supporting surface, beneath a lay of material to be cut; a thin upright standard B rising from the base; a circular knife C suitably journaled on the standard; andan electric or other suitable motor D supported by the standard and connectedby suitable gearing or drive mechanism (not shown) with the knife for rotating the latter. Only enough of the machine is illustrated in the drawings to give a correct understanding of the con struction and operation of the knife sharpener.

E E represent two emery or grinding wheels which are suitably journaled on hearing arms or members 10 and 11 adapted to move toward and from each other to place the two wheels into and out of grinding contact with the opposite faces of the edge of the knife. The grinding wheels are disposed relatively to each other and to the plane of the knife in a well known manner,

such that the wheels will be rotated by contact with the driven knife and will perform their function to the best advantage. In the construction shown the bearing arms 10 "andll are pivoted on fixed'studs or jour- 1131812 projecting from opposite sides of a support 13 which is adjustably mounted on the standard B, or other suitable part of themachine, so that thesupport can be adjusted to advance or retract the sharpener as may be necessary to cause the grinding wheels to contact with the knife nearer to or farther from the extreme edge. Each of the arms 10 and 11 is preferably adjustably secured by asplit. hub let and aclamping screw 15 to a sleeve 16 which is arranged to oscillate on one of the journals l2, and the two sleeves 16 are provided with intermeshing gear'teeth 1-7 whereby the two bearing arms are caused to swing simultaneously toward and from each other when the bean ing arm for one of the wheels is moved. The arm 11 is provided with an extension forming handle for swinging the wheels into and out of contact witl the knife. The

adjustable ccnnections between the wheel bearing'arms and their bearing sleeves enable the arms to be set on the sleeves so that the two wheels can be caused to simultaneously engage and'bear with the required pressure against the opposite faces of the knife edge.

Preferably, the adjustable support 13 for the sharpener is suitably pivoted at 18 on one side of the machine standard B and extends forwardly therefrom against the face of the standard, and is provided with a laterally projecting front. end or portion on which the bearing arms for the grinding wheels are mounted... The support is provided at its forward portion with a slot 19, curved concentrically with the pivot 18,

through which passes a clamping screw 20' fixed to the side of the machine, standard or frame. On this clamplng screw or stud 20' is a thumb nut 21 by which the support 13 is adapted to be clamped stationarily in adjusted positions. 22 indicates an adjusting screw which is suitably swiveled in the support 13 and turns in a threaded hole in a nut or member 23 which surrounds the clamping screw 20 between the thumb nut 21 and the support 18. By turning the adjusting screw 22, after first releasing the thumb nut 21, the support 18 can be moved to adjust the grinding wheels substantially in the direction of the plane of theknife toward and from the knife edge. This adjustment of the sharpener permits the grinding wheels to be set in the proper positions at opposite sides of the edge of the knife irrespective of the decreasing diame ter of the knife, due to wear. In the adjustment of the support 13 the grinding wheels move in an arc which passes substantially through the axis of the knife, and the wheels therefore occupy substantially like, angular relations to the knife in the various adjustments of the support.

scribed, while enabling the ready adjustment of the sharpenenprovides a very simis preferably secured to the support by screws 25 passing through slots in the shank H f the pointer, so that the pointer can be The support 7-13 pivoted and secured in the manner deproperly adjusted when applying the sharpener to a machine. The pointeror indicator extends from the support toward the knife and in the adjustment of the support .13

- moves in a plane substantially parallel with the sharpener for sharpening the knife, it

is only necessary to adjust the sharpener by means of the adjusting screw 22 until the end of the pointer is directly opposite to the circle of the edge of the knife. The operator is. thus enabled to accurately posit-ion the sharpener without relying on his own judgment or opinion as to the correct position of the grinding wheels and the sharpener can be quickly and accurately adjusted by the unskilled operatives who ordinarily use these cloth cutting machines, merely by fol lowing the simple direction to turn the screw 22 until the end of the pointer is opposite the edge of the knife. When thus adjusted the knife is sharpened by pressing the grinding wheels against the knife by means of the handle on the bearing arm 11. After using the sharpener, the grinding wheels are swung up to the position shown in Fig. 4 where they are releasably retained out of the way by the engagement of the screw 15 on the bearing arm 11 with a spring catch or holding device 26 on the support 13.

I claim as my invention:

1. In a cloth cutting machine, the combination with a driven knife, and a sharpening member arranged to contact with the knife for sharpening it, of means for adjusting said sharpening member relative to the knife so that the sharpening member will occupy like relations to the edge of the knife as the widthof the knife is lessened by wear, and an indicator'which has a fixed relation to the sharpening member and partakes in the adjustment of the sharpening member and indicates when in a prescribed position relative to the knife the corrct operative adjustment of the sharpening member.

2. In a cloth cutting machine, the combination with a driven knife, and a sharpening member arranged to contact with the knife for sharpening it, of means for adjusting said sharpening member relative to the knife so that the sharpening member will occupy like relations to the edge of the knife as the width of the knife is lessened by wear, and a pointer which is adjusted with the sharpening member toward and from the edge of the knife by the operation of said adjusting means and indicates the correct operative adjustment of the sharpening member when the end of the pointer is substantially opposite the cutting edge of the knife.

3. In a cloth cutting machine, the combination with a driven knife, and a knife sharpening member, of a support on which said sharpening member is mounted to move into and out of sharpening contact with the knife, means for adjusting said support to place the sharpening member in correct sharpening relation to the knife so that the sharpening member will occupy like relations to the edge of the knife as the width of the knife is lessened by wear, and an indicator which is connected to said support and indicates when in a prescribed position relative to the knife the correct adjustment of the sharpening member.

4. In a cloth cutting machine, the combination with a driven knife, and a pair of grinding wheels, of a support on which said wheels are mounted to move toward and from the plane of the knife into and out of contact with the opposite sides of the knife edge, means for adjusting said support in the direction of the width of the knife, 80 that the grinding wheels will occupy like relations to the edge of the knife as the width of the knife is lessened by wear, and an indicator which is connected to said support and is adjusted therewith and indicates when in a prescribed position relative to the knife the correct adjustment of said wheels.

lVitness my hand this 12th day of December, 1918.

FREDERICK J. CLARK.

Witnesses:

C. W. PARKER, A. L. MGGEE. 

